Glass container sidewall defect detection system with a diffused and controlled light source

ABSTRACT

Apparatus for inspecting glass containers in which an indexing starwheel moves a plurality of containers in series through a plurality of positions or stations where the containers are physically and optically examined. 
     One station, or position, is described in detail as the position where a glass container that is in a vertical position is rotated about its vertical axis by engagement of the finish thereof with a driven wheel. The container, as it is rotated, is viewed by a camera whose lens focuses the sidewall image of the bottle onto a vertical, linear array of light sensitive pick-ups in the camera. The camera is supported relative to the bottle handling system for adjustment up and down, back and forth and sideways so as to have the flexibility of viewing different size bottles. At the station where the sidewall of the bottles is to be inspected, a light source in the form of a tall housing is positioned in a vertical, annular recess of the starwheel. The light source is composed of three columns of five lamps plus a diffusion plate, with the outer columns being lit when viewing flint bottles and the center column is additionally lit when amber bottles are being viewed. The circuit for the lamps is provided with a means to detect the presence of burned out bulbs.

BACKGROUND OF THE INVENTION

In the operation of apparatus for the inspection of glass containers, itis assumed that automatic inspection may be made better than manual orvisual inspection by operators. This invention relates to an apparatusfor inspecting glassware and in particular to apparatus for inspectingthe sidewall of hollow glass containers for defects which are of anoptically distinguishable character. As might be expected, in themanufacture of blown hollow glass containers it sometimes happens thatthe sidewall of the container, that is that portion of the containerbelow the finish or neck of the bottle and above the curved heel andbottom of the bottle, has defects which would affect the performance ofthe container in service. It is important that every blown glasscontainer have its sidewall, among other portions of the container,inspected for defects and it would be a great advantage if thesecontainers could be inspected at high speeds with a high degree ofreliability so that when a container passes the inspection, it would bepositively free of defects in the sidewall thereof.

In the past, there have been inspection devices which would inspectcontainers for defects in the finish portion such as"line-over-finishes", "checks" (both vertical and horizontal), "seeds"and "blisters". Further, there have been bottom and heel check detectorswhich operate on the principle of optical reflectance or refraction.Furthermore, there have been inspection devices which inspected thecontainers to ensure that their height is correct, that the finish ofthe bottle is free of "dips and warps" and that the finish of thecontainer not be cocked or out of alignment with the general centralvertical axis of the container. Such an inspection apparatus may befound by reference to U.S. Pat. No. 3,313,409 issued to J. R. Johnsonand assigned to the Assignee of the present application.

The disclosure of this U.S. Pat. No. 3,313,409 is incorporated herein byreference thereto. A reading of this patent will indicate that there arefour inspection stations in the inspection device which are labeled II,III, IV and V. While the present disclosure is directed specifically tothe inspection of the sidewall area of a glass container, the inventionshould be considered in its broader sense as a system for inspecting atany one of the stations as depicted in the above-referred-to Johnsonpatent.

In the present disclosure, only one station of the inspection machine isdisclosed in detail, inasmuch as this is the station in which thecontainers are to be inspected for sidewall defects by the system of theinvention. While the Johnson patent is dealing with what would appear tobe fairly small size containers, the general principle of operation ofthe device is one which would readily lead itself to the handling of aplurality of larger size containers through a series of inspectionstations by having the ware brought to the machine with the turret orhead then being indexed through approximately a 45° angle of rotation.This indexing motion carries the containers in the present inventionthrough five inspection positions with a first position in advance ofthe first inspection station being in alignment with a conveyor thatbrings the bottles into the machine followed by five inspectionpositions and then followed by an exit position. Intermediate the exitposition and the entrance position is what is termed a "reject position"or zone where bottles which have been sensed as defective by theapparatus, are retained in the apparatus so as to be cleared from theapparatus turret at this intermediate position. At this position, acullet bin or other defective container disposal chute may bepositioned. Frequently, these bottles which are rejected are returned,by a suitable conveying system, to the forming area where the formingoperator may examine the container and in this way determine what mightbe an appropriate change to the process or to the machinery being usedto correct any ongoing or long-term defect which is being produced. Asin many manufacturing processes, defects sometimes crop up without anyapparent reason, while in other instances a defect may appear andcontinue to appear through a period of production. These types ofrecurring defects are those which the present invention is most capableof determining and alerting the operators to the situation. Furthermore,any glass container which is made with any kind of a structural defectwhich might affect its performance in the market place is gauged,inspected and discarded when such a defect is detected, no matter forwhat reason the defect may have been produced.

It will be noted that the starwheel or indexing mechanism head of theprior art shown in the above-mentioned U.S. Pat. No. 3,313,409 consistsgenerally of a pair of flat plates having notches formed in theperiphery thereof within which containers to be inspected are seriallyplaced. The starwheel of the present invention is considerably modifiedand improved for the purpose of handling containers in such a mannerthat they may be successfully inspected by illumination of the sidewallof the container to its full height. This is something which has notbeen easily achievable in prior devices where multiple inspections arebeing made. It has also been the practice in the past to move containersdown a conveyor and, in effect, use a pair of TV cameras looking at thebottle at two angles in an effort to determine whether or not acontainer is of an acceptable appearance or shape. One serious drawbackwith such a device has been the inability to completely examine 360° ofthe container sidewall without distortion being injected into the systemdue to the fact that the edges of the container produce opticalrefractance and reflectance aberrations in the images viewed by thecameras.

With the foregoing in view, it is an object of the present invention toprovide apparatus which is capable of moving glass containers through aseries of inspection positions where various types of inspection may becarried out, with one of the positions being the location of a noveloptical sidewall inspection device. Such sidewall inspection devicecomprises a source of illumination which will cover substantially thefull height of the container and illuminate a vertical section of thesidewall from behind. Further, the source of illumination is variable inits intensity to provide greater illumination for containers that areformed of colored glass such as "amber", and to vary the intensity ofthe light at selected areas of the bottle depending on the shapesthereof. In addition, the source is comprised of a plurality ofindividual lamps with means connected thereto for indicating when anylamp is burned out.

The illuminated sidewall is viewed by a camera that is mounted outboardof the handling system. The camera is composed of a linear array ofphotosensitive devices onto which the illuminated image of the sidewallsection is focused, with the array being scanned electronically and withthe outputs being processed by microprocessor.

It is a further object of the invention to provide a container handlingsystem capable of high speed operation and smooth handling of containersinto and out of the indexing head or starwheel. The invention furtherconsists of an improved starwheel construction which will permitrotation of a container at the sidewall inspection station withoutblocking the view of the camera and a novel mechanism to assist themovement of the containers out of the starwheel at the exit position.

Other and further objects will be apparent from the following detaileddescription taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

Apparatus for inspecting the sidewall of transparent containers foroptically detectable defects by having the container moved into aninspection position and rotated about its vertical axis. At theinspection position is located a stationary light source of sufficientheight to illuminate substantially the full height of the containerbeing inspected. The means for handling and rotating the container issuch that it does not block the back illumination of the container bythe light source which is formed of a plurality of lamps behind adiffusing plate. A camera with a vertical, linear array oflight-responsive pickups is positioned so that it may view theilluminated vertical portion of the back-lighted front wall of thecontainer being rotated and means are provided for monitoring theintensity of the light souce and for handling a series of containersinto and out of the inspection position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of the apparatus of the invention;

FIG. 2 is a plan view of the inspection of FIG. 1 on an enlarged scale;

FIG. 3 is a cross-sectional view taken at line 3--3 of FIG. 2;

FIG. 4 is a side elevational view of a portion of the containersupporting hub of the invention;

FIG. 5 is a view taken at line 5--5 of FIG. 4;

FIG. 6 is a plan view of the camera and support of FIG. 1 on an enlargedscale;

FIG. 7 is a cross-sectional view taken at line 7--7 of FIG. 6;

FIG. 8 is a side elevational view taken at 8--8 of FIG. 7;

FIG. 9 is a plan view of the exit station of the apparatus of FIG. 1 onan enlarged scale;

FIG. 10 is an enlarged view, partly in section, of the ejector actuatorshown in FIG. 9;

FIG. 11 is a schematic circuit diagram for the illuminating means of theinvention; and

FIG. 12 is a schematic circuit diagram for an alternative embodiment ofthe illuminating means of the invention.

The various aspects of the invention will be described in detail with anoverall view being given in a general bottle handling section followedby a sidewall inspection section which will include a detaileddescription of a container-illuminating system. Further, the containerexit position of the starwheel will be disclosed in light of themechanism shown in the drawings.

DETAILED DESCRIPTION OF THE DRAWINGS GENERAL BOTTLE HANDLING

With particular attention to FIG. 1, there is shown, in plan view, abottle inspection system for handling containers through a series ofpotential inspection positions and for determining the opticalcharacteristics of the sidewall region of glass containers specificallyat one position. Generally, the apparatus of FIG. 1 and the inspectionsystem thereof is of a similar character to that described in U.S. Pat.No. 3,313,409, and consists of a starwheel, generally designated 10, inFIGS. 1-3. The starwheel 10, in effect, is formed of a generallycylindrical hub 11 having a radially outwardly, extending portion 12 towhich are integrally formed downwardly extending arms 13 at spacedintervals about the periphery of the horizontally extending portion 12of the hub 11. The downwardly extending arms 13, adjacent theirlowermost portion, are provided with horizontally extending ledges 14which extend outwardly to a radial extent at which point there isconnected a downwardly extending arm extension 15. The downwardlyextending extension 15 in turn has an inwardly extending horizontalledge 16 formed thereto. The inwardly extending ledges 16 on the arms13, of which there are 8 in the present apparatus, serve as mounts forplates 17 which are attached to the lower surface thereof. Each plate 17extends horizontally outward from the sides of the ledge 16 to which itis attached and each plate carries a pair of bottle-engaging rollers 18,as best shown in FIG. 5. The downwardly extending arms 13 are providedwith a vertically elongated slot 19 therein, the slot 19 serving as anadjustable mounting means for bifurcated plates 20. The plates 20actually extend between adjacent arms 13. Each arm is provided with anangle bracket 21 which may be adjustable clamped to the arm 13 bysuitable fasteners such as bolt 22 as shown in FIG. 4. The bolt 22 willextend through the vertical slot 19 and have a nut or other suitablethreaded member on its opposite end. Loosening of the bolt 22 wouldpermit vertical adjustment of the bracket 21 relative to the arm 13.

As previously stated, the bracket 21 serves as a mounting platform forthe bifurcated plates 20. It should be understood that each plate 20 isconnected to a bracket 21 carried by adjacent arms. The mounting of theplate 20 to the bracket 21 may be by way of bolts 23, as shown in FIG.2. Each plate 20 carries a pair of rollers 24. The rollers 24 areadapted to engage the "finish" or threaded neck portion of a glasscontainer 25. The container 25 is shown in phantom line in FIGS. 3 and 4and in full line in FIGS. 1 and 2. It should be pointed out that theplates 20 have a cut-out portion in the center thereof when looking inplan view with the forward portion, designated 26, being of a size suchthat the neck of a bottle will fit in the gap formed thereby, while thecut-out portion closest to the hub 11 is cut out to a greater degree andgreater height for the purpose of permitting illumination of the bottleas will be later explained. Toward the rear portion of the cut-out 26are mounted the two neck-engaging rollers 24. As can be seen in FIG. 2,the rollers 24 are equidistant from a plane passing through the centerof the container positioned at the station shown in FIG. 2.

The hub 11 of the starwheel 10 is connected to a circular plate 27 bybolts 28. The circular pate 27 in turn is fastened to the upper end of adrive shaft 28. The drive shaft 29 is connected to a suitable indexingdrive which will turn the drive shaft and the hub or starwheel connectedthereto through a 45° angle of rotation during each indexing movementthereof.

With reference to FIG. 1, containers 25 are brought to the inspectiondevice in an upright position on a conveyor 30. The conveyor 30 ismoving in the direction of the arrow adjacent thereto and containers 25,as they approach the inspection device or the starwheel 10, are engagedby a screw 31. The screw 31 will be rotated at a preselected speed in aclockwise direction thus effecting the advancing movement of thecontainers 25 toward the center axis of the starwheel 10. The containersare confined to the threads of the screw by a guide rail 32. The timingof the screw is such that a container is brought into and becomesengaged by the starwheel 10 and the rollers 24 and 18 which arepositioned at each station of the starwheel at predetermined intervals.Indexing of the starwheel will carry the container which has beenpositioned in the confines or "pocket" of the starwheel to the nextadjacent position by indexing of the starwheel in a counter-clockwisedirection. In this fashion, containers are, one by one, moved through aseries of five inspection stations, only one of which is of specificconcern in the present invention and which is illustrated in greaterdetail in FIGS. 2 and 3. The starwheel 10, it should be noted, handlesthe containers through the series of five inspection stations and whenthe containers arrive at the location of an exit conveyor 33, thecontainers will be assisted in leaving the pocket of the starwheel so asto become engaged by a screw 34 which is being rotated in acounter-clockwise direction to effect removal of the containers from thestarwheel. Again the screw 34 is driven at a slightly greater velocitythan the velocity of the conveyor 33. While the threads on the screw 34are shown as symmetrical, they need not be of a regular pitch, but mayhave a greater separation distance as the screw becomes farther removedfrom the location of the starwheel 10. This is sometimes preferred whenclearing the inspection device and for spacing containers on the exitconveyor.

It should be noted that the containers, as they are moved through theplurality of inspection stations, which are five in number between theentrance conveyor 30 and the exit conveyor 33, are held within theconfines of the pockets in the starwheel by side-engaging rails 35 thatare at a height which will render the containers fairly stable as theyare moved laterally. Rails 35 are interrupted, obviously, at theentrance conveyor and at the exit conveyor so that the bottles may enterand exit from the starwheel. Furthermore, the rail 35 is not present ata portion of the distance between the exit conveyor and the entranceconveyor, since this is the zone where defective containers may berejected by being positioned into a chute 36. In the event, during anyof the inspections that may be carried out at the five stations wherethe containers are indexed to and between a defective bottle isdetermined to be present, a plunger 37 will be positioned by a cylinder38 connected thereto to move into position to prevent the defectivecontainer from leaving the starwheel during that period when thestarwheel is stationary and positioned in alignment with the exitconveyor 33. It can be seen that upon indexing of the starwheel with thecontainer still retained adjacent the exit position by the plunger 37,that the starwheel will carry the defective container to the area of thedisposal chute 36 and thus be discarded from the line of ware beinginspected, Immediately after initial indexing movement of the starwheelhas been sufficient to carry the deflective container into engagementwith the portion 39 of the guard rail, the plunger 37 will be retractedby the cylinder 38.

SIDEWALL INSPECTION

With specific reference now to FIGS. 2 and 3, a detailed description ofthe sidewall inspection system will be given.

The configuration of the starwheel is such that an annular, upstanding,recess 40 is provided therein within which serves as the location for anilluminating means generally designated 41. The illuminating meanscomprises a generally flat, vertically positioned panel 42 bolted to anangle bracket 43. The angle bracket 43 is supported from a horizontal,generally circular table 44. The panel 42 carries a plurality of fuseclips 45 in an array of three vertical columns with five individual clippairs in each column. Each clip supports a lamp 46. The lamp 46 is atubular bulb within which a vertically positioned filament is carried.These lamps are commercially available from General Electric anddesignated Style T-3, Lamp 211-2.

As can best be seen from FIG. 3, the lamps are positioned within agenerally trapezoidally-shaped housing having sidewalls 47. Thesidewalls 47, at their forward ends 48, are provided with verticalchannels 49 within which a light-diffusing plate 50 is positioned inoverlying relationship to all of the fifteen lamps. An opening isprovided in the portion 12 of the starwheel 10 to provide access to thediffuser plate from above, to permit elevation of the diffusing plate,when desired, for the purpose of replacing lamps which may burn outduring the operation of the device.

It should be noted that the illuminating means 41 extends below thetable 44 such that the lowestmost lamps wiill provide full heightillumination to the front side of a container positioned as shown inphantom line in FIG. 3. With the lights as shown in FIG. 3, the fullheight of the container 25 will be back-lighted and, in particular, thelower portion the bottle will be lighted. A vertical strip that islighted is viewable by a camera 51 mounted opposite the illuminatingmeans. The camera 51, as shown in FIG. 1, has a lens contained within ahousing 52. The area of view of the portion of the bottle beinginspected is schematically shown by dot-dash lines extending from thelens 52 to the area of the container in FIG. 1. The same pair ofdot-dash lines also indicate the area of view of the front portion ofthe bottle in FIG. 2. It should be pointed out that the camera lensfocuses that portion of the front portion of the sidewall of thecontainer that is within its view onto a vertical linear array ofpickups within the camera 51. The details of the camera and theelectronic processing of the signals resulting from scanning the pickupsin the camera is the subject of U.S. application Ser. No. 205,054 ofcommon Assignee with this application.

The vertical array of lamps used to inspect the sidewall characteristicsof flint or clear glass containers is provided by the two outer columnsof lamps 46 only. By providing a plurality of lamps, the forward wall ofthe container, which is that portion of the container being viewed bythe camera, will have a relatively constant intensity of illuminationover its total height and the width of the portion being viewed. Inorder to ensure that the entire container sidewall is inspected, it isnecessary that the container be rotated about its vertical axis throughat least 360° of rotation. Rotation of the container about its axis isaccomplished by a wheel 53 which has a frictional surface 54, such as arubber tread. The wheel is positioned in engagement with the neck of acontainer when the container is at the location shown in FIGS. 2 and 3.The wheel 54 is mounted on the upper end of a vertical shaft 55. Thelower end of the shaft 55, as viewed in FIG. 3, carries a pulley 56which is driven by a belt 57 in engagement therewith. The means fordriving the belt may take the form of an electric motor (not shown). Abracket 58 which carries a bearing 59 serves to support the shaft 55 forrotation about its vertical axis. It should be noted that the shaft 55and the wheel 53 are biased in the direction of the axis of the bottlein a yielding manner such that when indexing of the starwheel 10 takesplace, the neck of the container may pass from engagement with the wheel53 without undue stress placed thereon. However, it is necessary thatthe surface of the wheel engage the container neck with sufficient forceso as to assure rotation of the container about its vertical axis.

It should be noted that as the containers are moved around from stationto station, their bottoms slide on a stationary surface supported by thetable 44. To ensure that the bottle, when it is rotated about itsvertical axis, is maintained within the confines of the pockets of thestarwheel and in the position to be viewed by the camera 51, the siderail 35 is interrupted just in advance of the position where thesidewall inspection is being carried out. An auxiliary portion 60 (SeeFIG. 2) of the side rail is pivotally mounted to a bracket 61 which inturn is adjustably mounted to a fixed member 62 by a bolt 63 extendingthrough a horizontal slot 64 in the bracket 61. The rail portion 60 ismounted to the bracket 61 by a vertical pivot pin 64. The bracket 61also carries a stationary ear 65 into which a bolt 66 is threaded. Therail portion 60, at its end opposite the end where the pivot 64 isprovided, carries a right angle tab 67 with a portion that overlies theear 65. The tab 67 has a hole formed adjacent its end and the bolt 66extends therethrough with clearance from the tab 67. A compressionspring 68 extends between the head of the bolt 66 and the tab 67 to, ineffect, bias the tab and the one end portion 60 of the side rail intothe position shown in FIG. 2. A block 69 is mounted to the side of thetab 67. The outer end of the block 69 carries a roller 70. The roller 70is therefore biased by the spring 68 through the tab 67 and engages thesidewall of the container being inspected at the position shown in FIGS.1 and 2. In this way, the container is held at the side near its centerof gravity in engagement with the rollers 18.

It should be noted that in FIG. 3, a second dot-dash line configurationis shown for a container with the position of the angle bracket 21,steadying roller 24 and drive wheel 53 moved down to accommodate ashorter container designated 25'. For example, the bottle 25 wouldrepresent a 12 oz. beverage bottle such as a beer bottle, while 25'would represent a stubby or short beer or soft drink bottle. While therollers 70 and rail section 60 are shown in FIG. 3, it should beunderstood that these are merely shown for purpose of reference, sincethey normally would not be visible in this view when considering thesection line 3--3 designated on FIG. 2.

The camera 51, as can be seen with reference to FIGS. 6-8, is supportedon a vertical post 71, with the connection between the camera and thepost being such that the camera mount may be tilted in a vertical planerelative to the vertical axis of the post 71. The post 71 is clamped ina bracket 72 and thereby can be vertically adjusted or rotated relativeto the bracket 72. The lower portion of the bracket 72 takes the form ofa horizontal plate 73. The plate 73 carries a pair of clamping blocks 74at opposed ends thereof, which blocks, when threadably clamped at theends of the plate 73, will grip a pair of posts 75. The posts 75, attheir lower ends, are provided with feet 76 which may be verticallyadjusted by threaded screws 77. It should be understood that the feet 76rest upon the floor and through the adjustments shown, provide supportfor the camera at its position spaced from the starwheel 10. The plate73 is also adjustably carried by a plate 78 that extends to and mayconnect with the main support for the table 44 of the starwheelsupporting mechanism.

The plate 78, as viewed in FIG. 7, may be vertically adjusted byadjustment of a support column 79. A second angle bracket 80 is shownextending from the underside of plate 78 and it too may be connected toa stationary portion of the starwheel supporting mechanism.

One aspect of the present invention which has led to the design of thestarwheel with the arm extension 15 and two horizontal ledges 14 and 16so as to provide an outwardly extending area, is the provision at theexit position for an improved bottle exit assisting mechanism, generallydesignated 80, and shown in detail in FIGS. 9 and 10.

FIG. 9 shows the operative position of the assist mechanism and FIG. 10shows the internal detail of the spring-retaining and biasing means forthe assist mechanism. The assist mechanism takes the form of a bent,bottle-engaging member 81. Member 81 may be formed of a material whichhas a non-abrasive surface, yet has a high wear-resistance, for example,a Micarta member formed in the configuration shown and being generallyan elongated, rectangular arm. At one end, the member 81 isunrestrained, while at its opposite end it is fixed to a pivoted crank82. The crank 82 is pivotally supported for rotation about the axis of apin 83. The pin 83 is supported by a plate 84 which in turn is fixed tothe table 44. The plate 84 also supports a cylindrical housing 85 withinwhich a sleeve 86 is coaxially positioned. The sleeve 86 may beadjustably positioned relative to the cylindrical housing 85 byloosening of a threaded bolt 87. The sleeve 86 at one end thereof isprovided with a plug 88 which serves as a stop lock against which a head89 of a rod 90 may engage. The rod 90 is threadably connected to a crankarm 91 which in turn is pivotally connected to the crank 82. A threadedbolt 92 which may be turned in or out of the housing 85 adjustablylimits the position of the plug and sleeve 86 within the housing 85. Itshould be understood that the bolt 87 would be loosened during thisadjustment and tightened after the adjustment has been made. A set screw93 in the cylinder 85 is provided to maintain the adjusted position ofthe bolt 92, once the position has been selected.

It should be pointed out that with regard to FIG. 9, the member 81, infull line, is shown as being slightly turned in a clockwise directionwith respect to the dotted line position illustrated in FIG. 9. Thedotted position of the arm in FIG. 10 would correspond to the positionof the member 81, were the rod head 89 in actual engagement with theplug 88.

Before a container comes into position at the exit area of themechanism, shown in FIG. 9, a spring 94 in the sleeve 86 will maintainthe head 89 in engagement with the plug 88 and the member 81 will be atits farthest clockwise position with respect to its pivot. As acontainer is moved into the exit position shown in FIG. 9, the member 81will first assume the dotted line position, since the container will bebiased against the member and the spring 94 will be compressed to agreater extent than that viewed in FIG. 10. Once the container at theexit station is free to move out toward the screw 34, the spring 94 willcome into play and assist the container in its exiting movement.However, if the container has been judged or found to have a defect bythe gauging and inspection equipment, the plunger 37 will have movedinto position to block the exit of the container on the conveyor 33. Inthis event, the spring 94 will be held in a compressed position and themember 81 will be held in the dotted line position shown in FIG. 9 whereit will remain in engagement with the container while it is shifted byindexing the starwheel. The container is held in the starwheel by therail portion 39. When the bottle has cleared the rail portion 39, itwill be discarded by either being pushed from the table 44 or positionedover a cut-out provided in the table, as shown in FIG. 1, with thecut-out overlying the cullet chute 36.

As previously indicated, when the apparatus is being used to check thesidewall of flint or clear containers, only the outer two columns oflamps are illuminated. With this in view, reference may be had to theschematic wiring diagram illustrated in FIG. 11 wherein a source ofalternating current is shown connected to a transformer 95. Transformer95 has a dual secondary with grounded center taps and provides, throughrectifiers 96, a source of D.C. voltage for the lamps 46. The outputsfrom the rectifiers 96 are combined in a lead 97 which is connected inparallel to one side of the lamps 46 which are in the two outer columnsof five lamps each. The other side of these lamps are connected tocomparators 98 by leads 99. It should be understood that all of thelamps 46 are individually current sensed through separate comparators98. The comparators are supplied in groups of four in a unit which issupplied with power, schematically shown as lead 107, 107' connected tothe comparators that are in circuit with the outer two rows of lamps 46.In addition, when it is desirable to use the present inspection systemfor viewing the sidewall of amber bottles, where it is required to havea more intense illumination, a switch 100 may be moved downward by handto connect the power supply through a second lead 101 which is connectedto the input of the center set or column of lamps desginated 46'.

All of the lamps 46' are connected at their other sides to comparators98 of identical characteristic to those connected to lamps 46. Thecomparators that are in circuit with lamps 46' are supplied powerthrough lead 108 which is connected to the second lead 101. Thus thepower to the center row of lights and their comparators is controlled byswitch 100. A bias voltage provided in line 102 will feed a bias voltageinto each of the comparators through an equalizing circuit so as toprovide a biased voltage which is compared with the voltage output ofthe lamps. When the lamps are functioning, there will be no output fromthe comparators 98. The resistors 109 between the lamps and ground serveas current sensors to the lamps. When a lamp is burned out, no currentflows and, therefore, no voltage is developed across the sensor resistorto provide indication of fault. When a lamp malfunctions or burns out,then an output will be sensed from the comparators 98, which output isconnected by a lead 103 through a field effect transistor 104 to asuitable indicator or enunciator 105. The field effect transistor 104 isof the V-MOS type having very fast and very powerful response capable ofcarrying quite a bit of power and is also of fairly low resistance. Whenthe center column of lamps is illuminated by moving the switch 100, alamp 106 will light, providing a visual indication that the system isready to inspect the sidewall of amber colored bottles or containers.

The above described circuit is the power circuit for the preferred lampsystem.

A second embodiment of a circuit for supplying power to a modified lampsystem is shown in FIG. 12. In this embodiment, only ten lamps 110 areutilized as the back lighting arrangement for the bottle beinginspected. The ten lamps are physically arranged in two vertical rows offive lamps. With reference to FIG. 12, a source of alternating currentis connected to a transformer 111 whose output is connected throughrectifiers to input leads 112 and 113. Lead 112 is connected to tenthree-terminal positive voltage regulators 114, there being a regulator114 in the power supply to each of the lamps 110. The pair of regulators114 which are connected to the upper two lamps are connected as a pairby the output lead 115 of the first one being connected through aresistor 116 to the adjustment terminal 117 of the regulators. Theadjustment at the terminal 117 is effected through the potentiometer 118connected thereto to ground. Each of the pairs of lamps that are at thesame height are similarly adjusted as multiple pairs and thus theintensity of pairs of lamps may be effected by the hand adjustment,selectively of any one of the five potentiometers 118.

The output lead 115 from each regulator is connected to a comparator 119which is the same as is shown and described with respect to FIG. 11 anddesignated 98. The comparators 119 are again in groups of four with thepower thereto being derived through lead 120 connected to lead 112. Thecomparators are shown within enclosures designated 121, it beingunderstood that there are ten of these similar circuits all connected inparallel to the input or "OR" gate 122. The gate 122 may be a fieldeffect transistor as described in connection with FIG. 11. However, itshould be recognized that a bias voltage, derived from a voltageregulator 123, is connected through lead 124 to a faulty lamp indicator125 in a similar manner as described in connection with FIG. 11. Thusthe output at "OR" gate will provide a signal to the indicator.

We claim:
 1. Apparatus for inspecting the sidewall of glass containers,wherein the containers are presented at an inspection station, inseries, comprising:means at said station for rotating the containerabout its central, vertical axis; a diffuse light source positioned atone side of said station, said diffuse light source comprising anelongated lamp holder of a vertical height greater than that of thecontainers to be inspected, said source extending below the bottom ofthe sidewall so as to illuminate the opposed sidewall of the containerat the inspection station, an array of individual lamps, a diffuserpanel overlying said lamps, means connected to said lamps for varyingthe light output thereof, whereby the sensitivity of said camera outputmay be varied by varying the intensity of illumination at various pointson the container; a camera mounted adjacent said inspection station; andlens means on said camera focused on the illuminated sidewall of thecontainer, said camera having a linear, vertical array of photodetectors which are scanned while the containers are rotated.
 2. A lightsource for illuminating a transparent glass article for opticalinspection purposes comprising:a vertical support plate having a heightgreater than the height of the portion of the glass article to beilluminated; a plurality of lamp holders evenly spaced over the face ofsaid plate; a lamp mounted in each holder; spaced-apart sidewallsextending outwardly from said plate; a first vertically extending memberat the forward edge of one of said sidewalls; a second verticallyextending member at the forward edge of the other sidewall, said firstand second members being formed with vertically extending groovestherein in facing relationship; a light diffusing panel positioned insaid grooves extending the full height of said support plate; andcircuit means including a source of current connected to said lamps, andmeans in said circuit for varying the intensity of said lampsselectively.
 3. The light source of claim 2 wherein said circuit meanscomprises switch means for connecting the input voltage to selectivegroups of individual lamps of said plurality of lamps whereby theintensity of said source may be selectively varied.
 4. The light sourceof claim 2 wherein said lamp holders are in rows and columns.
 5. Thelight source of claim 4 wherein said lamp holders are in five verticallyspaced rows and three horizontally spaced columns.
 6. The light sourceof claim 4 or 5 wherein each said light holder is comprised of a pair ofbifurcated clips and said light bulbs are cylindrical bulbs withelongated filaments.
 7. In apparatus for inspecting glass containers forsidewall defects, where a light source is positioned to illuminate acontainer sidewall as the container is rotated and a linear array oflight-sensitive pick-ups are positioned to view the illuminatedsidewall, the improvement in the light source comprising:a verticalsupport plate having a height greater than the height of a container tobe inspected; three columns of five individual lamps mounted on saidplate; a pair of outwardly extending sidewalls connected to the verticalsides of said plate; an elongated, transparent light diffusing plate;means at the forward edges of said sidewalls for supporting said lightdiffusing plate in overlying relationship to said lamps, said lampsbeing of such an intensity in relation to said diffusing plate so thatthey do not present any significant deviation in light intensity acrossthe width or height of said diffusing plate circuit means connected tosaid lamps, said circuit means comprising parallel circuit means forenergizing the two outside columns of said lamps and switch means forselectively energizing the middle row of lamps when necessary toincrease the intensity of the light passing through the container. 8.The apparatus of claim 7, further including signal means connected incircuit with said switch means for indicating when the center column oflights is enerigzed.
 9. The apparatus of claim 7 further including meansin said circuit for indicating that any one of said lamps ismalfunctioning.